The Killing of a Sacred Deer (2017) is a film that behaves like a diagnosis delivered without emotion: calm, certain, final. Yorgos Lanthimos and co-writer Efthymis Filippou take a premise rooted in Euripides' Iphigenia and transplant it into a Cincinnati suburb, where a cardiac surgeon named Steven Murphy (Colin Farrell) has formed a strange, quasi-paternal bond with a teenager named Martin (Barry Keoghan). What begins as awkward social obligation becomes something inexplicable, then catastrophic. This is, quietly, one of the most unsettling films of the 2010s.
The Lanthimos method and why it works here
Lanthimos directs with a detachment that would read as affectation in lesser hands. His actors speak in a flat, overly literal register: no contractions early on, no emotional shorthand, no subtext seeping through inflection. Every line lands like a statement of fact, even when the facts are impossible. Steven's wife Anna (Nicole Kidman) tells her husband that she prefers "general anaesthesia" during sex. Martin describes his mother's attraction to Steven with the tone of someone reciting a grocery list. The effect is deeply, specifically wrong. It doesn't feel like stylisation; it feels like a world where something crucial about human connection has been surgically removed.
That's the method, and it's precisely calibrated for this story. The Killing of a Sacred Deer is about guilt and sacrifice, and Lanthimos needs you to feel the coldness of the moral geometry before the stakes become personal. By the time the horror arrives, you're already in the logic of it.
Barry Keoghan is the film's engine
Keoghan's Martin is one of the great horror performances of the past decade. The character is not supernatural. He doesn't have powers, exactly. What he has is a certainty that functions like power: a fixed belief in the justice of what he's proposing, delivered with the patient, slightly puzzled manner of a teenager explaining something obvious to a slow adult. When he tells Steven that one member of his family will die, then another, then another, unless Steven chooses one to kill himself, Keoghan doesn't play it as a threat. He plays it as information. That's what makes it so effective.
Farrell matches him with a performance that starts suppressed and ends wrecked. Steven is a man who has constructed his life on controlled competence: a prestigious career, a beautiful family, a hospital that defers to him. Martin is the thing his competence can't fix. Watching Farrell's composure erode incrementally is the film's real dramatic through-line, and it's far more disturbing than any explicit horror set piece.
The horror operates without gore
Lanthimos doesn't reach for blood or shock. The film's scariest sequences involve paralysis, not violence. Martin's curse begins manifesting physically in Steven's children: first they can't walk, then they stop eating, then their eyes bleed. None of this is explained. No mechanism is given. The hospital's best neurologists find nothing wrong. The film refuses the comfort of a rational frame. It presents the impossible with total, documentarian conviction.
This places The Killing of a Sacred Deer in a specific tradition. Like Midsommar (2019), it uses a folk-logic framework where the rules are internally consistent but utterly alien to modern secular rationalism. The horror isn't the monster. The horror is the logic itself, the fact that Martin's arithmetic is airtight, and the fact that Steven knows it.
Thimios Bakatakis's cinematography reinforces this. Wide-angle lenses distort space slightly, making rooms feel a few degrees off. The hospital corridors are shot with a cold institutional beauty. The Murphy family home is enormous and immaculate and feels like a place nothing organic could survive for long. Every frame is composed to maximize unease without a single element you could point to as wrong.
What the film is actually about
The mythological source material gives it away, but Lanthimos earns the resonance rather than borrowing it. This is a film about responsibility withheld and the price it extracts. Steven made a mistake in an operating theatre. A man died. Steven has never acknowledged what his culpability actually was, not to himself, not to the dead man's family. Martin is that unacknowledged debt made incarnate. The film doesn't frame this as a ghost story or a revenge thriller; it frames it as simple causality. You owe something. The bill arrives.
That thematic clarity is what separates the film from Lanthimos's more hermetically cold earlier work like Dogtooth (2009). The Killing of a Sacred Deer has a moral centre, even if the moral is delivered with zero consolation. It resembles Hereditary (2018) in that respect: a family horror film where the dread comes from the sense that something deserved is arriving, and no amount of love or money or surgical skill will stop it.
The final act
The climax is one of the bleakest images in contemporary horror cinema. Lanthimos stages it with a kind of flat procedural matter-of-factness that makes it more terrible than any amount of editorial embellishment would. The moment is ugly and ordinary and inevitable. It lands exactly as hard as the film has been preparing you for it to land.
Some viewers find the film too cold to care about. That objection misidentifies the temperature as a flaw rather than a formal choice. The film's coldness is its argument. Steven Murphy is cold. His world is cold. The warmth he hasn't shown to Martin's father is the exact warmth the film withholds from you. You feel its absence. That's not a bug. It's the whole structure.
The Killing of a Sacred Deer is Lanthimos at the height of his powers, using horror not as genre exercise but as the most honest language available for what he wants to say about guilt, consequence, and the terrifying tidiness of debt repaid. It's a precise, patient, and profoundly upsetting film. Watch it once. You won't need to watch it again to remember it.